Illuminating plant for vehicles, specially motor cycles



Oct. 21 1924. 1,512,105

K. KNAPP ILLUMIN ATING PLANT FOR VEHICLES SPECIALLY MOTOR CYCLES Filed April 25 1922 Patented Oct. 21, 1924.

UNITED STATES KARL KNAPP, OF HALLE-ON-THE-SAALE, GERMANY.

ILLUKINA'IING PLANT FO EI VEHICLES, SPMIALLY MOTOR CYCLES.

Application and April aa'laaa Serial No. 556,553.

To all whom it may concern:

Be it known that I, KARL KNAPP, a citizen of the German Republic, residing at Halleon the-Saale, Germany, have invented ccrtain new and useful Improvements in II- luminating Plants for Motor Vehicles, Specially Motor Cycles, of which the following IS a specification.

Electric illuminating plants for motor vehicles are already known in which the dynamo works together with a battery and with an automat1c cut-out for the return current from the battery. In order to dispense with special regulators working on constant voltage dynamos are used which by means of an exciting winding, put in shunt to an auxiliary brush, keep constant intensity of current at varying speed of the vehicle. These dynamos are constantly connected with the battery and charge the same during the travel always, also if the vehicle is running without illumination, as long as it is not cut out by a separate automatic device for limiting the charging. Without this device overchargin of the battery would be unavoidable. 5n the other hand an automatic cut-out is required, besides the devices for limiting the charging, which protects the dynamo against return current from the battery. A cut-out for the return current from the battery used in connection with a dynamo of other type has a voltage coil connected in parallel to the armature of the dynamo which is excited at the starting of the driving motor. The traction force of the spring acting upon the oscillable contact armature is in this case calculated so that it is overcome only at an excitation by the electromagnet which corre onds with the normal machine voltage. e contact lever closes the main circuit only at a number of revolutions of the dynamo which does no longer permit a return current from the battery. It the contact armature has connected the dynamo with the battery the full dynamo current is sent through a second coil, the so-called current coil. The contact armature is thus pressed still stronger upon the contact surfaces and reduces further the intermediate resistance. If new the number of revolutions of the dynamo decreases so that a return current from the battery would occur in the dynamo the current coil is no longer excited, as before, in the same sense as the voltage coil but, as the current has altered its direction in the meantime, in the opposlte sense. The comparatively weak field produced by the voltage coil is therefore weakened, as soon as the return current sets 1n, in such a manner that the tractron force of the spring becomes superior, whereby the main current is interrupted before a strong return current sets in.

A cut out for the return current has become known which works merely with one single coil to which only main current is supplied, said coil being neutralized by the battery return current flowing back through said 0011. This cut out would however, if it were inserted in the lighting plant of motor vehicles, attract its armature only so late that shocks occurring at the starting might, under certain conditions. prevent the closlngof the main current circuit.

Illuminating plants of this type are expensive and they are nevertheless submitted to frequent interruptions of service owing to the strong shocks which occur frequently in the motor vehicle service.

They require further, owing to the cut out for the charging current and to the twocoiled'thick cut-out for the return current, far too much space to be mounted upon small sized vehicles, and much less upon motor 0 cles, which are already overloaded.

This invention has for its object to provide a simple illuminating plant in utilizing the well known dynamo which keeps constant intensity of current with varying numbers of revolution, and which is not sensitive to shocks and so small that it can be easily mounted upon small motor cars and upon motor cycles.

With this object .in view the following measures have been taken: a

1. This dynamo, which keeps automatically constant intensity of current is so constructed and dimensioned that it produces current only if the vehicle is running with the lamp cut in, the battery being charged up so weakly that no automatic device for limiting the charging is required. 2. Instead of the well known two-coil cutout for the return current from the battery the return current from the battery being conducted in the manner known per se through said coil in opposite direction so that at the closing of the exciting circuit across the light-switch and the c011 the armature of the cut-out is strongly attracted at once at the starting and the product on of useful current is ensured notwithstanding the strong shocks which might occur.

Owing to the omission of a device for limiting the charging and owing to the selection of the cut out connected as described it has become possible to make the plant cheap, of small size but nevertheless secure in service.

An embodiment of an illuminating plant according to the invention is shown by way of example diagrammatically on the accompanying drawing.

At the armature a of the dynamo, besides the minus brush 6 and the plus brush 0, an auxiliary brush cl is applied in a manner known for the illumination and for the battery charging of'large sized motor vehicles with special starting motor and between this auxiliary brush d and the plus brush 0 an exciter f is applied in shunt circuit.- A constant intensity of current isthus ensured for the dynamo from a determinedminimum travelling speed on. The dynamo is inthelnain current, must' be made of the thick wound and constructed, according to the-in vention, 1n such a manner that it efiects,

small switch box which can be easily fixed at the rear of the battery box, in front of the cyclist.

The illuminating plant operates as follows 1. Voyage at day time: The light switch it is in the open position indicated in dash lines in which current is neither produced nor can it be supplied from the battery to the consumers.

2;. Voyage at night time: If the switch is broughtto the closed position shown in full lines, current flows, as long as the motorcycle is stopped, in the direction of the arrows 1 from the battery m through the lead I a to the terminal Z, across the bridge h to the terminal Z, through lead n'to the lamps g, g, to the mass of the cycle and back to the battery. The lamps burn, being fed from the battery.

At'thestarting the exciting current is developed in being rapidly strengthened in the direction of the arrows 2. It flows from the plus pole 0' through the lead. is to the terminal 2', across bridge h to terminal 2" and thencethrough thecoil la of the electromagnet and through theexciter winding f V acrossthe auxiliarybrush at back to the plus polec. 'As the coilk', which is also inserted besides the feeding of the current consumers 'fore only little space. The space usually 9', 9', only a weak charging of the battery.- g If the dynamo would be used for charging mlzed as no voltagecod is produced. Owing quires much space, is very sensitive and consequently dangerous for. the illuminating plant, the light switch his inserted-{according to the invention, between the connecting terminals 1', i of a lead k, which is, in accordance with the invention,- common for the exciting circuit and for the main cir cuit, and the connecting terminals Z, Z of the lead n, n which conducts fi'om', thebattery on to the lamps or other current con sumers g, g. By the switch arms it the metallic switching bridges it are iiisulated the one from the-other. In a fundamentally novel manner the well known single coil-k'I "occupied-by the voltage coil is also econoto-the suppression of the separate voltage coil which hitherto short-circuited the main terminals of the machine always, also at the starting, the exciting current is increased more rapidly and to greater intensity than otherwise. 7 The small magnet coil k gencrates therefore in'the core 0 of the magnet 5 immediately at the beginning'of the voyage suchfgreat attracting-force'that the oscillable armature r is strongly attracted, the spring u beingput under tension, and that the contaets a, s is'securedly closed. With the contacts 8,8 the main circuit is closed also so that-the main current flows first in the direction. of the arrows 3 in the-same wire and infthe same direction as the excitin current across the coil .70, but then across t e armature to the lead 'rt'ofs the'battery, across contact 1, switching. bridge: 12;, contact Z, lead n, lanips g, g and mass back to the minus pole et is-iforlnedby theb. The main current which flows also 1 :thronghafthe coilk" increases still further the magnetismof the core a so that the contact: i s-strongly pulled against contact 8 enemas contacts cannot be separated even by. the 1 strongest shocks.

lead 11.. A sprmg u tendsto separate-e the motor cycle is running with the lowest continuous speed the dynamo The switch and the cut-out'for the return dimes-a Small excess, of current over the curcurrent can be both accommodatedfinra rent consumed by'the lamps, this excess ourrent flowing in the direction of the arrows 3 into the battery: The battery is thus feebly charged continuously, during the night voyage so that it will be sufiicient to feed the lamps during the stops.

3. Stopping of the cycle: In this case the battery current flows finally in the direction Z through the lead t, the contacts a, a, the armature r, the support p of the armature, coil k, terminal i, switching bridge h, terminal 2', plus pole a, minus pole b and mass, back to the battery. The battery current is predominant over the exciting and main currents which become gradually feebler and flows in coil is in opposite direction as these currents until the magnet core 0 becomes neutral and spring it pulls the armature with its contact 8 away from contact 8' so that the return current is interrupted. The lamps are supplied with current only from the battery.

If the cycle is started again the above described process repeats itself, viz the exciting current fiows first throu h the exciting circuit which is still closed so that the armature is attracted and the contact closing is strengthened by the main current which recharges the battery.

I claim I An illuminating plant for motor vehicles, specially for motor cycles, with dynamo, battery and automatic cut-out for the return current from the battery, the oscillating armature of which cut-out closes the main current circuit of the dynamo electro-magnetically and interrupts the same by spring action directly before the contact is established if the vehicle is started, comprising in combination a dynamo of well known type, an auxiliary brush, an exciter winding applied in shunt connection to said auxiliary brush so that the dynamo keeps the 3am}:

intensity of current also if the spec travel varies, said dynamo roducing a quantity of current slightly in excess of the current consumed, a battery, a single coil "cut-out, a light switch designed to close simultaneously the battery circuit for the lamps and the exciting-circuit which goes across the single interrupter coil and the field winding, said dynamo working together with said battery, single-coil cut-out and 1i ht switch in such a manner that over one o? the bridges of the light switch the exciting current circuit is first closed across the single magnet coil and the armature of the cut-out connected between the cut-out coil and the field winding is strongly attracted at the be inning of the travel, so that the closing 0? a main circuit is effected which passes through the same lead with the exciting current to behind the magnet coil,

whereupon said main current is connected by the armature of the cut-out and its contacts with a batteryand consumer-circuit .ada ted to be closed only across the other brici g e of the light switch, the contact pressure of the armature being-simultaneously increased, and that, if the vehicle stops, all the circuits, with the exception of the battery-consumer circuit, are interrupted by the return'current from the battery in the single coil.

In testimony whereof I afiix my signature in presence 0 two witnesses.

' KARL KNAPP. Witnesses:

D. Mtrrn, CARL H. Miiuma. 

